The firm also said it had diverted nearly all (97%) of the 428,000 tonnes of demolition and construction waste generated by the project away from landfill, while 98% of eight million tonnes of excavated material removed during tunnelling work had been “beneficially reused” in an number of agricualutral and environmental projects, including three million tonnes going towards creating an RSPB bird reserve on Wallasea Island in Essex.

The man-made scheme at Wallasea Island opened two years ago and attracts tens of thousands of migratory birds,

While costs on the cross-London rail route, known as the Elizabeth Line, have rocketed, Andrew Wolstenholme, Crossrail’s chief executive, said the group was expected to meet its sustainability targets, which included reducing emissions from construction machinery to improve air quality.

Meanwhile, nine structures had been completed to date with each achieving a post-construction rating of ‘excellent’ under the Civil Engineering Environmental Quality scheme.